The present invention relates to portable spreaders of the broadcast kind which are supportable on a pair of wheels and which are manually pushed by the user thereof.
A spreader of this kind is disclosed in the U.S. Pat. No. 5,288,017 to Havlovitz, assigned to the assignee of the present invention, which disclosure is incorporated herein by reference. In the Havlovitz patent there is shown an articulated spreader having pre-assembled parts, including upper and lower frames having divergent leg members that can be assembled for use by the operator without the need of tools. The Havlovitz patent uses a manual pull cable for controlling the rate of flow of material from the spreader hopper, an accordion-like shut-off plate for opening and shutting the material exit escape at the bottom of the hopper, and a gear box housing disposed below the broadcast rotor plate.
In the case of the construction of a shut-off plate above-mentioned there is a need for providing a simple and efficient design which uses a minimum of moving parts and is reliable in operation. In the case of controlling the rate of flow of material from the hopper, there is a need also for a control mechanism which can vary the flow rate of material with both ease and a high degree of accuracy, and in the case of a gear box design, the heart of any broadcast spreader design, there is a need for a simple and efficient design with a minimum of moving parts that will allow error-free operation.